This page is draft materials for an eventual OGF Experience Document describing interoperability testing with IBM DFDL.
Not everything here will make it into the final report. Some things will be too minor to note.
Public DFDL Schemas
These schemas are published, and are interoperable:
- CSV
- NACHA
- ISO8583
- QuasiXML
- GeoNames
- IBM4690TLOG (as of 2019-05-17 - development branch)
- HL7-v2.7 - An older revision, no longer maintained by IBM, was tested and is interoperable.
- EDIFACT
- MagVar
The following schemas are published, but need minor adjustments for portability, including possibly documentation edits on the DFDLSchemas web site materials.
- vCard (needs unordered sequences feature. See
The following schemas are published, but make use of features available in only Daffodil, and so are not expected to interoperate:
- PNG
- PCAP
- mil-std-2045
- BMP
- GIF
- NITF
- JPEG
- shapeFile
The following schemas are listed on DFDLSchemas, but are available only under license from IBM, and are not candidates for interoperability testing:
- HIPAA-5010
- SWIFT-MT
- HL7 - maintained versions
Non-Public DFDL Schemas
These schemas are available only to those with access to DI2E.net or Forge.mil; however, as that is a substantial community of users, we also document interoperability for these schemas here:
Portable (works on Daffodil and IBM DFDL)
- cef - common-event-format - works for parse and unparse.
- army_drrs - works for parse and unparse.
- uscg_ucop - Works for parse and unparse.
Expected Non-Portable - works only on Daffodil due to use of Daffodil-specific features
- agnosc_remedy - schema makes use of asserts that invoke dfdl:checkConstraints - not supported by IBM DFDL (as of 2019-05-28)
- Was tested for parse with these asserts removed. - Parse gives error separator not found. However, it is not expected that this would work.
- VMF - uses dfdl:inputValueCalc and dfdl:outputValueCalc extensively, as well as dfdl:bitOrder="leastSignificantBitFirst"
GMTIF - uses dfdl:inputValueCalc extensively
- USMTF - A few small tests pass, but this schema makes extensive use of backtracking via assertions which invoke dfdl:checkConstraints - not supported by IBM DFDL (as of 2019-05-28)
Eventually Public DFDL Schemas
These schemas are restricted access pending permission to make public. Their status w.r.t., portability is as noted.
- iCalendar - uses dfdl:inputValueCalc (daffodil only as of 2019-05-28) - possibly this could be removed.
- IMF - unknown
- IPFIX - fully portable
Test Suites
Test Suite 'daffodil-test-ibm1'
This test suite is part of the Daffodil source tree, but can be run against IBM DFDL using a cross tester.
All tests in this suite run portably on Daffodil and IBM DFDL. (2019-05-17 development branch).
A few tests are conditionalized and run on only one or the other due to specific features that Daffodil has, or that IBM has.
Daffodil Test Suite 'daffodil-test'
This is a larger test suite.
Of 3172 tests, 1866 are skipped either because they are negative tests (which are not being evaluated because diagnostic messages vary so widely), or because they use DFDL features known not to be implemented by IBM DFDL such as dfdl:inputValueCalc and dfdl:outputValueCalc, or hidden groups.
That leaves 1306 tests.
202 tests pass as of 2018-12-10.
1104 fail as of 2018-12-10
Common Test Failures To Be Resolved
The vast bulk of the failures can be explained by a small number of structural problems with the test suite or test infrastructure:
- daf:error - function obviously not supported by IBM DFDL.
- Many daffodil tests put constructs on global elements that are not allowed on global elements by DFDL.
- Many tests have namespace errors - root elements of infosets are not in the proper namespace. (commonly this is the ex or http://example.com namespace)
- Missing properties (textBooleanTrueRep/FalseRep being undefined is one)
- Mixing of invalid schema errors in the same test suites with other tests.
- Different defineSchema inside a TDML file are not being isolated - compile errors in one stop all tests in that TDML file from compiling.
- This is a TDML Runner issue and just how tests are authored.
- Incorrect property syntax: extraEscapedCharacter="%#WSP*; ..." for example
- Missing properties: textBidi, textPadKind, textTrimKind, escapeSchemeRef, documentFinalTerminatorCanBeMissing, and many others are missing from test environments.
Incompatibilities
- test_timeFunctions01 - IBM DFDL does not support dfdl:calendarTimeZone="" (empty string, meaning 'no time zone')
- This is problematic because the default format most tests use has this property defined this way.
- TBD: Perhaps tests should choose from the normal daffodil default formats, and one designed for compatibility??
- dfdl:calendarPattern contains more than 3 "S" symbols. (Should be a warning? - possible bug in cross-test rig)
- separator and escapeCharacter cannot include the same value - this is tolerated by Daffodil. (Allows a delimiter to be escaped by doubling it.)
Incompatibilities Which May be Daffodil Bugs
- When type is long, int, short or byte, DFDL property 'binaryNumberRep' must not be 'bcd' as this cannot have a negative value. (testBCDCharset01)
- IBM DFDL insists on signed types not being BCD since it has no way to represent negative values.
- Daffodil tolerates not having emptyValueDelimiterPolicy set, if it can show there is no concept of "empty" for the definition. This is not portable because the rules in DFDL are simpler than this. The property simply is required if terminator is defined. (or initiator), regardless of whether there is any notion of empty for a type.
- truncateSpecifiedLengthString - missing
- trailingSkip - missing
- alignment - missing